A Chinese passport holder with a US visa has a flight scheduled from Beijing to Los Angeles in mid-November.

This person wants to go to South Korea for a 3 day conference; the conference is one week prior to the PEK-LAX flight.

If this person buys a round-trip ticket from China to Korea, will the transit visa be sufficient? Or will they need a regular visa?

Extra info:

What if the original ticket were modified to make it ICN-PEK-LAX?

Some Transit Information Here. It says "Holding a confirmed onward flight ticket for departure within 30 days." Would a return ticket to China than a flight to LAX a week later be sufficiently "onward"?